Motion picture photography usually involves much changing of the height and position of the camera between shots. With the conventional motion picture tripod, every change of height necessitates adjusting each of the three legs individually, meanwhile supporting the weight of the tripod plus the weight of the camera, which is often very considerable. The process frequently has to be repeated several times because of the difficulty of attaining an exact height under such awkward circumstances.
The tripod is generally used with a three-armed base commonly called a "triangle" in the trade (although it is not triangular but star-shaped) which serves to keep the legs from spreading too far. In use, the triangle must first be spread on the floor, and the points of the tripod legs inserted in small cups on each arm of the triangle. This is extremely difficult to manage without getting down to floor level and putting the points in place at close range. Then the points must be secured by one means or another, usually involving much turning down of set-screws, a job which must also be done at floor level. With many triangles these set-screws must be loosened and then re-tightened every time tripod height is changed.
Whenever the camera is moved any distance, the entire assemblage--camera, tripod, and triangle--must be picked up bodily and carried. Frequently the triangle falls off at this point, whereupon the whole process must be gone through again.
When a shot near floor level is needed, the camera and the tripod head must be removed from the legs, the legs removed from the triangle, a set of short legs attached to the triangle, and the camera and tripod head attached to these legs. When the shot is finished the whole process must be gone through again in reverse.
All of these time-consuming (and thus exceedingly expensive) inconveniences can be eliminated totally or reduced drastically by the addition to the conventional tripod of the modifications proposed here.